Sunnyvale, California — (November 13, 2012) — Spirent Communications, a leader in network testing, services and devices, today announced that Isocore, an independent technology validation, certification and product evaluation lab, used Spirent solutions for Leading Edge Code testing involving key features such as MPLS-TP, Multicast-VPN (mVPN), Software Defined Networking (SDN) and IPv6. This public test, conducted at Isocore's lab in Washington D.C., showcased the readiness of MPLS and SDN technologies to support carrier transport and core networks.

"Working with test partners such as Spirent on public interoperability tests, we are helping to demonstrate how carrier and equipment vendors accelerate the pace of MPLS-TP & SDN rollouts while reducing costly post-deployment failures," said Dr. Bijan Jabbari, president of Isocore.

"New technologies don't work in a vacuum. One of the most crucial tests for SDN and MPLS-TP is the interoperability of vendor equipment with the widely deployed IP/MPLS networks," said Rajesh Rajamani, senior product marketing manager at Spirent Communications. "Spirent has been a leader in MPLS-TP testing and offers a broader range of network topology emulation capabilities that help vendors bring products to market faster with fewer post deployment issues."

About Spirent Communications plc
Spirent Communications plc. (LSE: SPT), a global leader in test & measurement, inspires innovation within development labs, networks and IT organizations to enable customers to deploy communications networks, services & applications, and devices that enrich life. Our extensive portfolio of solutions test data centers, high speed Ethernet networks and services, 3G/4G wireless networks and devices, network security, and global navigation satellite systems. With solutions used by more than 1,700 customers in 30 countries, the world’s largest equipment manufacturers, service providers, enterprise and governments rely daily on Spirent to help ensure their success. Based in Sunnyvale, CA, Spirent Communications has 1,300 employees worldwide.

Spirent Communications plc Ordinary shares are traded on the London Stock Exchange (ticker: SPT). The Company operates a Level 1 American Depositary Receipt ("ADR") program with each ADR representing four Spirent Communications plc Ordinary shares. The ADRs trade in the US over-the-counter ("OTC") market under the symbol SPMYY and the CUSIP number is 84856M209. Spirent Communications' sales to the United States government are made through Spirent Federal Systems Inc (www.spirentfederal.com).

Spirent, Spirent Communications and the Spirent logo are trademarks or registered trademarks of Spirent Communications plc. All other trademarks or registered trademarks mentioned herein are held by their respective companies. All rights reserved.

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